From 97ab802aa36f1ee74196525af0e844656ae3dc63 Mon Sep 17 00:00:00 2001 From: Marek Szyprowski Date: Thu, 18 Feb 2021 11:33:16 +0100 Subject: [PATCH] adc: meson-saradc: add support for getting reference voltage value Add support for getting the 'vref-supply' regulator and register it as ADC's reference voltage regulator, so clients can translate sampled ADC values to the voltage. Signed-off-by: Marek Szyprowski Reviewed-by: Simon Glass Signed-off-by: Neil Armstrong --- drivers/adc/meson-saradc.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/drivers/adc/meson-saradc.c b/drivers/adc/meson-saradc.c index 21db55831d..1a45a3a265 100644 --- a/drivers/adc/meson-saradc.c +++ b/drivers/adc/meson-saradc.c @@ -18,6 +18,7 @@ #include #include #include +#include #define MESON_SAR_ADC_REG0 0x00 #define MESON_SAR_ADC_REG0_PANEL_DETECT BIT(31) @@ -656,7 +657,10 @@ static int meson_saradc_stop(struct udevice *dev) static int meson_saradc_probe(struct udevice *dev) { + struct adc_uclass_plat *uc_pdata = dev_get_uclass_plat(dev); struct meson_saradc_priv *priv = dev_get_priv(dev); + struct udevice *vref; + int vref_uv; int ret; ret = regmap_init_mem(dev_ofnode(dev), &priv->regmap); @@ -675,6 +679,23 @@ static int meson_saradc_probe(struct udevice *dev) priv->active_channel = -1; + ret = device_get_supply_regulator(dev, "vref-supply", &vref); + if (ret) { + printf("can't get vref-supply: %d\n", ret); + return ret; + } + + vref_uv = regulator_get_value(vref); + if (vref_uv < 0) { + printf("can't get vref-supply value: %d\n", vref_uv); + return vref_uv; + } + + /* VDD supplied by common vref pin */ + uc_pdata->vdd_supply = vref; + uc_pdata->vdd_microvolts = vref_uv; + uc_pdata->vss_microvolts = 0; + return 0; }